Ruby on Rails Developer

Ruby on Rails Developer
Based-in: Vietnam
Employment Type: Part-time Remote (-4 days per week)
About Sunbytes
Sunbytes is a fast-growing Tech and Talent Solutions company built on collaboration, innovation, and trust. With offices in Vietnam and the Netherlands, we deliver high-quality software development, dedicated team setups, and strategic recruitment services for international clients. At Sunbytes, we combine technical excellence with a people-first approach - empowering both our partners and our talents to achieve sustainable success.
About the Opportunity
Sunbytes is looking for a mid-level Ruby on Rails Developer, who will be joining an innovative logistics start-up based in the Netherlands, focused on fast, on-demand, and zero-emission building material delivery operating across six Dutch regions.
The web platform has been evolving over the last four years. You will collaborate directly with the lead developer to increase development velocity, refactor key features, and prepare the infrastructure for mobile integrations.
Key Responsibilities
Full-Stack Development: Handle end-to-end task execution across both back-end logic and front-end user interfaces.
Feature & API Engineering: Implement tasks ranging from simple UI updates (e.g., booking form fields) to complex core business features (e.g., pricing API logic, route management).
Mobile App Integration: Assist in building and exposing secure API endpoints to connect the Rails back-end with driver mobile apps via platforms like Draftbit.
Quality & Testing: Write, maintain, and push fully unit-tested code independently to ensure platform stability.
Codebase Maintenance: Navigate and continuously optimize an established 4-year-old codebase within an existing CI/CD pipeline.
Requirements
Job Requirements
Technical Skills
Framework: Solid, hands-on experience building and maintaining applications with Ruby on Rails.
Front-end: Proficiency with Stimulus JS and vanilla JavaScript.
Integrations & APIs: Proven experience connecting third-party services-specifically Google Maps APIs and OpenAI endpoints-as well as managing custom RESTful APIs.
Infrastructure & DevOps: Familiarity with Heroku, AWS, and working inside established CI/CD pipelines.
Collaboration Tools: Comfortable using Notion for async communication, documentation, and task management.
Qualifications & Soft Skills
Seniority & Autonomy: Strong Mid-Level capability. Must be able to take ownership of tasks and push production-ready code with minimal supervision (juniors excluded due to team bandwidth).
Adaptability: Comfortable working within existing multi-contributor codebases.
Modern Tooling: Encouraged to utilize AI coding tools (e.g., GitHub Copilot, Cursor) to navigate and accelerate development within the codebase efficiently.
Communication: Clear verbal and written English communication for async and sync team alignment.
Benefits
Working Setup & Terms
Flexibility: Remote-first arrangement with flexible working hours.
Timezone Requirement: Must offer 5 to 6 hours of overlap with European time zones (UK/Netherlands) for regular syncs and check-ins.
Contract: Month-to-month flexibility with a 30-day probation period to evaluate fit and code delivery quality.
Benefits
A challenging and supportive work environment with opportunities to develop your career
A dynamic and international team, providing a great career journey